A lens that never touches the cornea.
A scleral lens is a large rigid lens. It arches over the cornea and rests on the white of the eye. The space underneath holds a layer of saline, which gives an irregular cornea a smooth optical surface.
- Diameter
- 15–20 mm
- Rests on
- The sclera, the white of the eye
- Underneath
- Sterile, unpreserved saline
- Used for
- Keratoconus, corneal grafts, severe dry eye
How a scleral lens is fitted
One drawing, five stepsMap the surface.
A scan measures the shape of your cornea and the white of the eye around it. The lens is designed from this map.
Clearance drawn about 4× actual depth for legibility.
Who it helps
Keratoconus
When the cornea is too irregular for glasses or soft lenses to give clear vision.
After a graft or surgery
When a corneal graft or earlier surgery has left the surface uneven.
Severe dry eye
The saline layer keeps the cornea covered and wet while the lens is worn.
What the fitting involves
Sequence / 04Assessment
Your vision, corneal health and what you've tried before.
Mapping
The shape of the cornea and sclera is measured.
Trial lens
A diagnostic lens is worn and checked at the slit lamp once it settles.
Your lens
A custom lens is made. You learn to put it in, take it out and care for it.